Carburetor for internal combustion engines



July 28, 19'36- s. SURRA 2,049,180

CARBURETOR FOR INTERNAL COMBUSTION ENGINES Filed Feb. 14, 1935 v 2 Sheets-Sheet l Il l'.

July 28, 1936. s. sURRA 2,049,180

CARBURETOR FOR INTERNAL COMBUSTION ENGINES Filed Feb. 14, 1935 2 Sheets-Sheet 2 Patented July 28, 1936 foNro stars CARBURETOR FOR INTERNAL COMBUSTIONv y ENGINES Stphane Surra, Chambery, France- Application February 14, 1935, Serial No. 6,492

In France March 19, 1934 3 Claims.

' kInv ordinary carburetors the main jet disposed stationary in the admission inlet only gives its fully delivery i; e. is situated in the Zone of maxivmum suction when the butterfly valve or the like Yis fully opened.

For intermediary running positions its deliver is defectiveV owing to the fact that the zone of suction istransferred to the level of the restrictions of the butterfly valve or the like which it follows and in which the jet is not disposed owing toits stationary position.

l The improvements according to the present infvention have chiefly for object to overcome this inconvenience.

15. For this purpose this carburetor comprises, apart from its slow running jet, amultiplicity of .jets which come-into action one after the other step by step, as the shutter (butterfly valve or the like) opens, but which, as soon as they come .201 intoaction, are in a zone of maximum suction so '25 livery vcorresponds with that of the single jet ordinarily used in present day carburetorsand .the respective delivery of each one of them is likelwise calculated according to the degree of opening 4,of the shutterraccording to which it respectively 30Qcomes into action.

;`.The invention also has for object numerous Viurther vfeatures which will be readily understood by referring to complementary description which follows, reference being had Vto the accompany- 5- ing drawings which, both the description and .drawings naturally are given solely by way of example, and'refer to a carburetor comprising three main jets and a slow running jet.

In these drawings, Figures 1 and 2 are two views of a carburetor seen respectively in elevation and in section on the line I-I and 2-2 of Figure 3.

Fig. 3 is a plan view of the body, the buttery valve or the like being shown in ldotted lines fully opened, the cover and the air inlet tube being removed.

Fig. Liris a corresponding side elevation of the jets, the valve body being removed.

50 Fig. 5 is a cross section of the air admission pipe taken on the line 5 5 of Fig. 2.

According to the invention this carburetor comprises a float chamber 2 to which the gasolene is admitted through the pipe 3 the constant level 55 of same being ensured as usual by a float 4.

` communication hole I5.

The float chamber is in communication through pipes 26 with the jet chamber 6, 6', E of the main jets l, l', l" of which there are three shown in the example.

These jets which have their outlets in the v5 Vpipes 8, 8', 8, in communication through the intermediary of a turnable valve body 9 with the flange I il for connection to the manifold of the motor, have three holes II and are each disposed in passages I2, I2', I2 within which air can lo Yenter through the channels of` passages I3, I3',

the atmosphere through a pipe I9.

This pipe isrprovided with a partition or wall 2 9 forming' a communication chamber through the intermediary of a regulating shutter or baie r2 I` actuated at 22, with a hot air larm pipe 23.` 25

The slow'running of the motor, turnable valve 'body' being closed, is obtained by means of the jet 24, mounted on a jet chamber in communication with the oat chamber 2 by means of a passage 26. This jet delivers into a superposed passage-2l. Between them the air can enter at 3 0 and a hand adjustable screw threaded nut'28 permits of adjusting thisair passage 30, the said screw threaded nut 28 being secured after adjustment by a 35 lock hut 29.' V

A second air inlet at I'3" operates under the same conditionsas do -theparts I3, I3', 13" on vthe jets 1, l', 'I".

On the pipe 21 which has its outlet at the ange 40 I0 beyond the valve body 9, is intercalated a needle valve 3l which can be adjusted by means of a nut 32 which can be secured in position by means of a lock nut 29'. The spindle of this needle valve which is actuated by a spring 33 45 bears on this nut through the intermediary of an eccentric lever 34 actuated at 4I.

Finally a stirrup piece 35 oscillating at 3S and provided with an abutment bolt 3l, ensures the tightness of the joint 39 for the float chamber 2, 50 which carries the whole of the jets with the body proper 38 of the carburetor.

To dismantle the jets 24, l, l', 'I'l it is only necessary to loosen the plugs 4D, 40', 4H, 40' forming the ends of the jet chambers 25, 6, 6', 6". 55

opening up of the carburetor, in the direction of the arrow, its pipe I5 first uncovers the jet 1 then I3', I3 and by the holes II, energetically mixes the gasolene before it is drawn into the motor,

The delivery of each of these jets l, 1', 'I" is adjustable by a needle oripointed screw actu-Y ated by hand and the movement of which is braked by a spring. v y y Similarly, each of the jet chambers 6, tf, 6

fills with gasolene whenthe corresponding jetv is not in action and so forms a reserve of spirit which enables rapid accelerations to be made.

In regard to the slow running jet 24, theen-V try rof air to whichl is adjustable by hand by means ofthe nut-28 without necessitating any tool, it forms at the same time a compensating means for filling the vacuum Vwhich occurs at the commencement of the opening of the'valve body V9 before the jets 'I, 1', and I comelinto action.

This slow running adjustment may be manually regulated according to the external temperature by meanspfthe needle valve 3l -which can be lifted temporarily when starting up by means of a lever 34 in order to completely uncover the passages 21 and I3" and without the adjust-4V ment being altered. i

The air inletpipe I9 avoids the noise of the suction whichoccurs with ordinary carburetors land its wall. 20 with adjustable shutterv 2| Vallows the admission of hotair through the Ypipe 213 rso giving a better output and facilitating starting up.`l Y f YThe dismantling of the float chamber 2 is simvp1@ anarapid and with itthe VWhole of the jets and the jetV chambers can Ybe removed.

Finally asis obvious and as wi1lhave already been seen, the invention is in no way limited to the single example of constructionl described ab-ovenorto that of its different parts but Von .the contraryitycomprises all variations in con- .structioncomprising the application of; simila means. v ,1-

1.` A carburetor comprising in combination 'a pair of interi'ltting. superposed sections, the lower said float chamber section,jet Vtubes extendingV Thus the valve body 9 being actuated at the upwardly in said bosses above thetops 'thereof and communicating'with said respective carbureting chambers of said bosses, a series of air supl c ply nipplesjcarried by said upper section radially thereof and communicating With said valve cham- 5 i ber, each of said air supply nipples having a hole into which one of said jettubes projects, a valve in said Valve chamber and movable to serially establish communication between said nipples and valve chamber, and means for holding said intertting carburetor sections assembled.

`2. A carburetor comprising in combination a pair of intertting superposed sections, the lower f section providing a float chamber and the upper Y section providing av valve chamber substantially l5 aligned with said float chamber, a plurality of independent upwardly Vextending carbureting chamber-providing bosses disposed radially on said float chamber section,rjet tubes extending upwardly in said bosses above the tops thereof 20 and communicating with vsaid respective kcarbureting chambers` of said bosses, a series of air supply nipples carried by said upper section radie vallythereof and communicating with said valve said'respective jet tubes carried by said"nipples, 3.0`

and means for holding said intertting carburetor sections' assembled. i*

3. A carburetor comprising in combination a pair of intertting superposed sections, the lower section providing a ilo-at chamber and the up- ,35 per section providing a valve chamber substantially aligned with said oat'chamber, a plurality of independent upwardly extending carbureting t chamber-providing `bosses disposedA radially lon upwardlyinV said bosses abovethe topsthereof" and communicating with said respectivecarbureting chambers of lsaid bosses, a series of air supply nipplescarried by'said upper lsection radially thereof and communicating with said 'valveicljiain-L ber, each of said air supplynipples having aholeY` into which one of said jet tubes projects, a valve in said valvechamber and movable to-serially establish communication between said nipplesand valve chamber, said'jet tubes being spacedV from of said uppersection, said jet? tubesv having lair, inlet holes below the upper ends of said'bosses whereby to provideV an 4auxiliary airY inlet"for` each jet tube, and meansfor holding said intertting carburetor sections assembled.

,SURE/A; sTrfHANn the walls of vsaid bosses above 4saidV carbureting Y,chambers thereof, and the; upperends of` said bosses-being spaced from said air vinlet nipples 

